Perhaps you should try some spelling variations:
boi thuong » moi truong, hoc thuong, doi tuong
hanh khoa » hang khoa, anh khoa, hanh hoa
khach dao » sach dao, khach san, khac do
khoan boi » khoan hoi, khoan bai, khoan nhoi
sach dai » sach dao, sach bai, sach dat
thu hanh » thuc hanh, thu thanh, thuy hanh
vu khach » vu khanh, vu khac, vay khach
dao thuc » dan thuc, dao tuc, do thuc
thuc cac » thuc cach, tuc cac, phuc cac
te sach » toc sach
dai thu » dai thua, dai thuc, doi thu
khoa he » hoa he, khoa hoc, khong he

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: (( te sach dai thu hanh khoa he thong ) or ( vu khach dao thuc cac khoan boi thuong ))~.
• If you are trying to use Boolean operators, they must be ALL CAPS: (( te sach dai thu hanh khoa he thong ) OR ( vu khach dao thuc cac khoan boi thuong )).
• Adding a wildcard symbol may retrieve word variants: (( te sach dai thu hanh khoa he thong ) or ( vu khach dao thuc cac khoan boi thuong ))*.